Macroscopic dynamics near the isotropic-smectic-A phase transition.

The hydrodynamic theory for the smectic-A phase and the isotropic phase is generalized to the macroscopic dynamics in the vicinity of the isotropic-smectic-A phase transition. The macroscopic dynamic equations are presented on the isotropic side as well as on the smectic-A side of the phase transition, incorporating the effect of an external electric field. Specific experiments to test some of the effects contained in the macroscopic dynamic equations are suggested.